{ diff(x1, t) = (1*k1*(k2*k56*x2 - k3*x1) + (-1)*k1*k38*x1)/k1,
  diff(x2, t) = ((-1)*k1*(k2*k56*x2 - k3*x1) + 1*k1*k52 + (-1)*k1*k53*x2)/k1,
  diff(x3, t) = (1*k1*k4*x1*x4/(k5 + x4) + (-1)*k1*k6*x3 + (-1)*k1*k26*x13*x3/(k27 + x3))/k1,
  diff(x4, t) = ((-1)*k1*k4*x1*x4/(k5 + x4) + 1*k1*k6*x3 + 1*k1*k26*x13*x3/(k27 + x3))/k1,
  diff(x5, t) = (1*k1*k7*x3*x6/(k8 + x6) + (-1)*k1*k9*k59*x5/(k10 + x5))/k1,
  diff(x6, t) = ((-1)*k1*k7*x3*x6/(k8 + x6) + 1*k1*k9*k59*x5/(k10 + x5))/k1,
  diff(x7, t) = (1*k1*k11*x5*x8/(k12 + x8) + (-1)*k1*k13*k58*x7/(k14 + x7) + (-1)*k1*k36*x17*x7/(k37 + x7))/k1,
  diff(x8, t) = ((-1)*k1*k11*x5*x8/(k12 + x8) + 1*k1*k13*k58*x7/(k14 + x7) + 1*k1*k36*x17*x7/(k37 + x7))/k1,
  diff(x9, t) = (1*k1*k15*x7*x10/(k16 + x10) + (-1)*k1*k17*k57*x9/(k18 + x9) + 1*k1*k50*x24*x10/(k51 + x10))/k1,
  diff(x10, t) = ((-1)*k1*k15*x7*x10/(k16 + x10) + 1*k1*k17*k57*x9/(k18 + x9) + (-1)*k1*k50*x24*x10/(k51 + x10))/k1,
  diff(x11, t) = (1*k1*k19*x9*x12/(k20 + x12) + (-1)*k1*k21*k57*x11/(k22 + x11))/k1,
  diff(x12, t) = ((-1)*k1*k19*x9*x12/(k20 + x12) + 1*k1*k21*k57*x11/(k22 + x11))/k1,
  diff(x13, t) = (1*k1*k23*x11*x14/(k24 + x14) + (-1)*k1*k25*x13)/k1,
  diff(x14, t) = ((-1)*k1*k23*x11*x14/(k24 + x14) + 1*k1*k25*x13)/k1,
  diff(x15, t) = (1*k1*k28*x1*x16/(k29 + x16) + 1*k1*k30*x5*x16/(k31 + x16) + (-1)*k1*k32*x15)/k1,
  diff(x16, t) = ((-1)*k1*k28*x1*x16/(k29 + x16) + (-1)*k1*k30*x5*x16/(k31 + x16) + 1*k1*k32*x15)/k1,
  diff(x17, t) = (1*k1*k33*x15*x18/(k34 + x18) + (-1)*k1*k35*x17)/k1,
  diff(x18, t) = ((-1)*k1*k33*x15*x18/(k34 + x18) + 1*k1*k35*x17)/k1,
  diff(x19, t) = (1*k1*k38*x1 + 1*k1*k53*x2)/k1,
  diff(x20, t) = (1*k1*k39*x1*x21/(k40 + x21) + (-1)*k1*k41*x20)/k1,
  diff(x21, t) = ((-1)*k1*k39*x1*x21/(k40 + x21) + 1*k1*k41*x20)/k1,
  diff(x22, t) = (1*k1*k42*x20*x23/(k43 + x23) + (-1)*k1*k44*k60*x22/(k45 + x22))/k1,
  diff(x23, t) = ((-1)*k1*k42*x20*x23/(k43 + x23) + 1*k1*k44*k60*x22/(k45 + x22))/k1,
  diff(x24, t) = (1*k1*k46*x22*x25/(k47 + x25) + (-1)*k1*k48*k58*x24/(k49 + x24) + 1*k1*k54*x5*x25/(k55 + x25))/k1,
  diff(x25, t) = ((-1)*k1*k46*x22*x25/(k47 + x25) + 1*k1*k48*k58*x24/(k49 + x24) + (-1)*k1*k54*x5*x25/(k55 + x25))/k1,
  diff(x26, t) = 0,
  diff(x27, t) = 0,
  diff(x28, t) = 0,
  diff(x29, t) = 0,
  diff(x30, t) = 0,
  diff(x31, t) = 0 }